1. Field of the Invention
The present invention relates to an absorbent article which is fixed to an undergarment and which absorbs vaginal discharge, menstrual bleeding, urine, or the like, and particularly relates to an absorbent article in which a plurality of absorbent components can be layered and bonded together, the absorbent component on top can be peeled off after use, and the absorbent component under the top component can be used.
2. Related Art
A composite menstrual sanitary product in which a plurality of composite absorbent sheets is layered so as to be able to peel apart is known as a menstrual sanitary product for absorbing blood that is discharged from a woman's vagina. When this composite menstrual sanitary product is used, the composite absorbent sheet that is the bottom layer is fixed to the inside surface of an undergarment, and the composite absorbent sheet that is the top layer is placed against the area of discharge. After the blood flow has been absorbed for a prescribed period of time by the top-layer composite absorbent sheet, the top-layer composite absorbent sheet is peeled off and discarded, and the composite absorbent sheet that is disposed under the discarded layer is placed against the area of discharge. The number of times that the absorbent product must be changed can thereby be reduced.
For example, in the composite absorbent sheets described in Japanese Laid-open Patent Application No. 2001-187084, the bottom-layer composite absorbent sheet and the top-layer composite absorbent sheet are each composed of a lining sheet, a surface film, and a liquid-absorbent sheet sandwiched between the lining sheet and the surface film. In each composite absorbent sheet, the aforementioned lining sheet is formed so as to be larger than the surface film, and the lining sheets of the top-layer composite absorbent sheet and bottom-layer composite absorbent sheet are bonded together by heat sealing or a pressure-sensitive adhesive layer.
The aforementioned lining sheets are bonded together along the periphery of the composite absorbent sheet, and an area is formed in a portion thereof in which there is no bonding. The top-layer composite absorbent sheet can easily be peeled from the bottom-layer composite absorbent sheet by inserting a finger into this area.
The conventional composite menstrual sanitary products described in Japanese Patent Application No. 2005-134648 and other publications use a stack of composite absorbent sheets having the same structure. Therefore, when the top-layer composite absorbent sheet is used after being placed against the discharge area, there is a tendency for kinks or wrinkles to form in the bottom-layer composite absorbent sheet as a result of body or undergarment movement. When the top-layer composite absorbent sheet is peeled off, the bottom-layer composite absorbent sheet adheres to the discharge area instead of the top-layer composite absorbent sheet. When the bottom-layer composite absorbent sheet is kinked or wrinkled at this time, the adhesion of the bottom-layer composite absorbent sheet to the discharge area is easily compromised. As a result, the article becomes uncomfortable to wear when the bottom-layer composite absorbent sheet is fitted, and there is also a risk of leakage of blood and the like.
When the top-layer composite absorbent sheet is used after being placed against the discharge area, the bottom-layer composite absorbent sheet is in a compressed state for a long period of time due to bodily pressure exerted on the top-layer composite absorbent sheet. The bottom-layer composite absorbent sheet is therefore likely to be in a crushed state due to the contamination of the top-layer composite absorbent sheet when this top-layer composite absorbent sheet is peeled off. As a result, the bottom-layer composite absorbent sheet becomes uncomfortable to touch when it is placed against the discharge area of the body, and the ability of the bottom-layer composite absorbent sheet to absorb liquids is diminished.
In the conventional composite menstrual sanitary products described in Japanese Laid-open Patent Application No. 2001-187084 and other publications, the top-layer composite absorbent sheet and the lining sheet of the bottom-layer composite absorbent sheet are bonded together. The top-layer composite absorbent sheet is therefore difficult to peel off when the bottom-layer composite absorbent sheet is fixed to the undergarment. As a result, there is a risk of the bottom-layer composite absorbent sheet being separated from the undergarment when the top-layer composite absorbent sheet is peeled off.
Since the bonding portion of the lining sheet is located at the edge of the composite menstrual sanitary product, this bonding portion can easily cause skin discomfort when it comes in contact with the skin during fitting.
The bottom-layer composite absorbent sheet and the top-layer composite absorbent sheet also have the same appearance, and are difficult to distinguish from each other. Therefore, with this type of composite menstrual sanitary product, when the user observes during fitting that the product has absorbed blood or the like and become contaminated, the user may be unable to correctly distinguish whether the top-layer composite absorbent sheet or the bottom-layer composite absorbent sheet has been used. This is likely to cause inconvenience in the sense that the user may peel off from the undergarment and discard both the top-layer composite absorbent sheet and the bottom-layer composite absorbent sheet regardless of the fact that the bottom-layer composite absorbent sheet has not been used, or may peel the product from the undergarment without preparing a replacement menstrual sanitary product, even though the bottom-layer composite absorbent sheet is being used.